Metal-melting furnace



G. C. RAHN.

METAL MELTING FURNACE.

l APPLICATION FILED NOV. .10, i919.

Patented Jan. W, 1922.

llll

GEORGE G..RAHN, F ERIE, PENNSYLVANIA.

METAL-ll/IELTING FURNACE. i

messes.

Application filed November 10, 1919.

To aZZ whom it may concern Be it known that I, Gnonen C. RAHN, a citizenof the United States residing at Erie, in the county of Erie and Stateof Pennsylvania, have invented new and useful Improvements inMetal-Melting Furnaces, of which the following is a specification.

This invention is designed to so arrange a metal melting furnace that itmay be used with a crucible or as an open flame furnace. It alsoinvolves improvements in the closure for the furnace and the dispositionof the fumes. It further involves a convenient means for replacing thecrucible support.

The invention is illustrated in the acconr panying drawings as followsFig. 1 shows a side elevation.

Fig. 2 a front elevation, partly in section.

Fig. 3 a part of the bottom of the furnace with a closure substitutedfor the support.

The furnace chamber is made up of the lining l and usual casing 2. Thefurnace chamber is closed at the bottom as shown. Trunnions 3 are formedon the casing and these operate in bearings 1-. The bearings are carriedupon upright-s 5 on the frame 6. A gear 7 is fixed on one of thetrunnions and this meshes with a gear 8. The gear 8 is carried by ashaft 9, the shaft 9 being mounted in bearings 10 and a hand wheel 11 isfixed on the shaft 9 by means of which the furnace may be readilytilted.

A crucible 11 rests on an insulating plate 12. The plate 12 is supportedby a metal post- 13, the post being surrounded by an in sulatingmaterial 14. A removable plate 15 is secured to the bottom of the casingand an asbestos gasket 17 is arranged on the up per side of the plateclosing the joint. The post 13 is screw-threaded at 18 and the screwthread operates in the plate 15 so that the support may be adjusted andremoved. Means for a cooling medium such as air is provided through thepipes 19 which enter the post 13. I

The removable plate carrying the crucible support permits of the removalof this support so that new insulating material may be readily provided.This removable feature also permits of the substitution of a mereclosure plug 20 with an insulating block 21 as shown in Fig. 3 when itis desired to use the furnace as an open flame furnace.

I prefer to provide the lining with an off-set 22 around its upper edge.This more Specification of Letters Patent.

T PQ F f? 11 Arm t terrier...

Patented Jan. it

Serial No. 336,960.

thoroughly protects the metal and the joint with the cover. The off-setis provided with a pouring notch 23 as clearly shown in Fig. 1.

The main cover 2-1 is provided with a flange 25 on its under side. Thecasing is provided with a seating ring 26. The flange has the tongues 27and the seating ring has the grooves 28 by means of which it doubletongue and groove joint is provided for the cover. Insulating material29 is retained in place on the cover by means of the flange 25. A cover30 closes the crucible opening. It has a downwardly extending flange 31.The cover 2 1 is provided with a seating ring 32 arranged with groovesand the flange 31 has the tongues 33 which seat in the grooves. Aninsulating material 34 is held in place by the flange 31. In thisconstruction as with the main cover there is a double grooved seat forthe cover which more effectually prevents the outflow of fumes.

One of the trunnions is provided with the fuel pipe 35 and air pipe 35.The other trunnion is provided with a fume discharge outlet 36. A plate37 is hinged at 37 on the trunnion and locked at 38. This has a lining39 with a restricted opening 40. The open ing 40 may be varied byvarying the lining 39, or if desired, the plate 37 may be dropped downthus leaving the fume opening unre stricted. In this way the fume outletmay be restricted as desired thus controlling the velocity of thedischarge of fumes. A pipe 11 is arranged in alinement with the opening4:0 and the pipes 42 and 43 lead from the pipe 41, these being providedwith the dampers 44.- and 45 respectively. By controlling the dischargeof fumes the oxides which are carried off with the fumes may be saved inwhat may be a bag-house. Further the fumes are prevented from escapingtothe furnace room, many of such fumes being detrimental.

What I claim as new is 1. In a metal melting furnace, the combination ofa tilting furnace chamber; a crucible support extending upwardly fromthe bottom of the furnace; and a removable plate secured to the bottomof the furnace carrying said support, the bottom of the furnace chamberbeing closed by said plate, the opening so closed affording an openingthrough which the crucible support may be inserted.

2. In a metal melting furnace, the combination of a tilting furnacechamber; a crucible support extending upwardly from the bottom of thefurnace, said support comprisinga metal post and insulating materialsurrounding the post; and a removable plate secured to the bottom of thefurnace carrying said support, the bottom of the furnace chamber beingclosed by said plate, the opening so closed affording an opening throughwhich the crucible support may beinserted.

' 3. In a metal melting furnace, the combination of a tilting furnacechamber; a crucible support extending upwardly from the bottom of thefurnace, said support comprising a metal post and insulating materialsurrounding the post; and a removable plate secured to the bottom of thefurnace carrying said support, the post of said support being removablefrom the plate, the bottom of the furnace chamber being closed by saidplate, the opening so closed affording an opening through which thecrucible support. may be inserted.

4. In a metal melting furnace, the combination of a melting furnacechamber comprising a gasket and a lining therefor, the the lining havingan inwardly extending offset around its upper periphery.

In a metal melting furnace, the combination of a melting furnace chambercomprising a gasket anda lining therefor, the lining having an inwardlyextending offset around its upper periphery, said off-set being providedwith a pouring notch.

6. In a metal melting furnace, the combination of a furnace chambercomprising a lining and a gasket; a cover for the furnace having aflange extending therefrom; and

a lining Within the flange, said cover and gasket having a jointcomprising a plurality of tongues and grooves.

7 In a metal melting furnace, the combi nation of. a furnace chamberhaving a gasket and a lining; and a cover for the furnace, saidconnection having a plurality of tongues and grooves.

8. In a metal melting furnace, the combination of a furnace chamber; andtrunnions on the chamber, one of said trunnions having a fume outletopening for the furnace.

9. In a metal melting furnace, the combination of a furnace chamber;trunnions on the chamber, one of said trunnions having a fume outletopening for the furnace; and a restriction provided for the opening.

10. In a metal melting furnace, the combination of a furnace chamber;trunnions on the chamber, one of Said trunnions having a fume outletopening for the furnace; and a removable restriction for the fumeoutlet.

11. In a metal melting furnace, the combination of a furnace chamber;trunnions on the chamber, one of said trunnions having a fume outletopening for the furnace; and a fume pipe in alinement with the outletopening. V

12. In a metal melting furnace, the combination of a furnace chamber;trunnions on the chamber, one of said trunnions having a fume outletopening; a restriction in said outlet opening; and a fume pipe inalinement with the opening.

In testimony whereof I have hereunto set my hand.

, enonen o. RAHN.

